The present invention relates to an apparatus for displaying grouped characters in a scanning type display. More specifically, the present invention relates to an apparatus for displaying characters for a television game by the use of a scanning type display such as a cathode ray tube.
With a recent development of microelectronics and a microcomputer, a television game machine capable of providing various types of games by the use of a television receiver has become popular.
In playing a game with such a television game machine, a plurality of characters are first displayed in an initial condition and a moving symbol such as a ball is displayed to move on the screen, while a position controllable symbol such as a racket is displayed on the screen such that a player hits and repulses the moving symbol with the position controllable symbol through manual operation of a control knob for the position controllable symbol in order to make the moving symbol collide with one of the characters. When the moving symbol collides with any one of the characters, the display of said one character is extinguished. The number of the characters as thus extinguished is counted to keep the score. The score is also displayed and a game is played by the score.
In order to display characters on the screen of a cathode ray tube of such a television game machine, a so-called video random-access memory may be used. It has been a conventional common practice that a video random-access memory comprises a plurality of storing regions corresponding to the picture elements of a picture frame of a cathode ray tube. As is well known, when a display is made using a cathode ray tube, a picture frame is scanned in the horizontal direction and in the vertical direction with an electron beam. According to the Japanese televison standard, one picture frame comprises 262 lines and the horizontal scanning is performed by way of interlace scanning. Let it be assumed that the horizontal line is divided into say 114 to consider one picture frame as comprising a plurality of picture elements arranged in rows and columns. Therefore, it was required that a conventional video random-access memory comprises a number of bits commensurate with the number of the product (114.times.262=29868) obtained by multiplication of the number of divisions in the horizontal direction (114) by the number of divisions in the vertical direction (262) as the storage capacity of the memory. The stored information is read out bit by bit during the horizontal scanning and the vertical scanning and each time the logic one representing that display is to be made at the position corresponding to a given bit, is read, a display is made in the corresponding region on the screen of a cathode ray tube. Thus, the logic one is written in a plurality of bits or storing regions in a random-access memory corresponding to a respective plurality of picture elements constituting a configuration of a character to be displayed. As a result, it was required that a conventional video random-access memory comprises a considerably large storage capacity. Hence, such a video random-access memory was expensive and accordingly a game machine utilizing such a conventional random-access memory was also rather expensive.
In playing such a display game, an arrangement of characters being displayed need be returned to the initial condition to be ready for the following play or game, after one play or game is ended, so that the characters as extinguished in the previous play or game may again be displayed. To that end, a conventional game machine comprises a read-only memory for fixedly storing a predetermined pattern of characters to be attained in the initial condition. The read-only memory also comprises a plurality of bits corresponding to a respective plurality of picture elements constituting a configuration of a character being displayed, which necessitates an increased number of bits and thus also a large storage capacity. Accordingly, a read-only memory for such an arrangement pattern of characters also became expensive. Therefore, if it is desired that a configuration of a character is changeable, a read-only memory of a larger storage capacity was required.
In some type of conventional television game machines, a microcomputer has been utilized and the generation of signals for displaying a moving symbol such as a ball, a position controllable symbol such as a racket, and the like, detection of collision of the moving symbol with one of the characters, and the like have been achieved by respectively programming a microcomputer. However, a conventional video random-access memory and a read-only memory of a larger storage capacity as described above have increased the number of steps of control operations performed by a microcomputer and thus required a microcomputer of a higher speed and of a larger scale or capacity. Accordingly, a conventional game machine using a microcomputer became much more expensive.
In some cases, it is desired that the configuration of a character per se is changeable depending on the kinds of games or in order to increase an interest in a game, thereby to provide a much more interesting game machine. However, in order to change a configuration of a character per se being displayed using a conventional video random-access memory, it was necessary to load information associated with the character configuration as a plurality of bits into the video random-access memory corresponding to the changed character configuration. Typically, such a change of a character configuration is performed by way of programming or software processing by a microcomputer. Accordingly, a game machine capable of changing a character configuration became much more complicated and expensive. Thus, a conventional apparatus for providing display information to display grouped characters in a scanning type display became complicated and expensive as compared with an apparatus employing the present invention.